Control valve



March 13, 1945.

F. G. G. ARMSTRONG CONTROL VALVE Filed March 11, 1943 n im m mow Pateiiie Mar. 13, "1945 man CONTROL VALVE Fullerton George Gordon Armstrong, Beverley, England Application March 11, 1943, Serial No. 478,806 In Great Britain January 1, 1943 1 Claim.

The present invention relates Ato an improved assembly of two oppositely acting pressure re- I ly compensate for differences in fluid viscosity, or

again where it is d-esired to vary the flow pastthe valve according to differences in temperature of the uid.

The invention and the advantages thereof will be understood from the following description of a. typical embodiment with reference to the drawing in which there is shown an assembly of two oppositely acting pressure release valves partly insection and partly in elevation, with one valve partially open.

Anassembly f two oppositely acting pressure release valves for controlling' the ow of uid comprises a hollow casing 23 whose interior is divided into two parts by a valve seat 2I1dening a port between said parts.

Bores 24 and `2b serve as connections for fluid to the right and'left hand parts (as shown) respectively of the interior of the casing 23.

A spindle I extends from one part of the casing interior into the other part and carries a member 4 which is axially bored so as to ilt on and be displaceable along the spindle and is axially counterbored to form a passageway 6 and radially bored to form a passageway li. The member 4 has a Valve seat 9 formed on the end thereof and the passageways 6 and 5 provide a means for conducting fluid from the left hand p-art of the casing interior to the valve seat 9.

Coaxially formed with respect to the valveseat 9 is a valve head 2U which is conical in shape and complementary to the seat 2| in the casing.

A face,of an enlarged portion 2 on the spindle I provides an abutment against one end oi which a non-rigid thermal responsive tubular element 3 makes contact. The element 3 is made of soft material not capable of taking stress without deformation and loosely surrounds the spindle I. The other end of element 3 makes contact with member 4. IA sleeve ofvmetal '2B forms a rigid support which surrounds the non-rigid element 3 and prevents distortion thereof in a radial direction due to the action of heat.

An element l is bored so as to be a sliding t along spindle I and carries a valve head which is complementary to the seat 9- on the member 4.

Spring 8, Whose pressure is adjustable by knurled nut I0 on a screwed end portion I I of the 55 spindle I urges the element 'l along the spindle towards the seat 9 on the member 4.

. The pressure exerted by spring 8 on element 'I when the valve head on element 'I and the complementary seat 9 on member 4 are in any given relative position depends on the position along spindle I of member 4, which position is determined by the effect of temperature on the thermal responsive element 3.

A spring 22 acts between the end wall of the left side of the interior of the casing and the face of enlarged portion 2 of spindle I opposite to that face against which element 3 bears and urges spindle I together with element 3, sleeve 26, member 4 and other components carried thereon in the direction of the right hand side of the interior of 'the casing towards a position wherein the valve head 20 on member 4 makes contact with the seat 2| in the casing.

Thus the pressure of spring 22 on the spindle and consequently the force with which valve head 20 is urged towards seat 2| is, for any given relative position of the Valve head and valve seat, varied in accordance with temperature.

The reason for such variations of` spring pressure, arising from thermal expansion or contraction of element 3 diierentially measured with respect to the spindle, is quite obviously due to the interior is divided into two parts by a valve seat defining a port, a connection for uid in each of the parts ofthe casing, a spindle extending from one part of the casing into the other part thereof, a member having a valve head complementary to the valve seat aforesaid and a valve seat coaxially formed on the member with respect to said head with means to conduct fluid through the member to the valve seat thereof carried by and displaceable along the spindle, an abutment on said spindle, a non-rigid thermal responsive tubular element loosely surrounding said spindle and having its ends in contact respectively with said abutment and said member, a rigid support surroundf ing said non-rigid element, an element displaceable along said spindle carrying a valve head complementary to the valve seat on said member, spring means carried by the spindle urging said valve head carrying element along the spindle towards the valve seat on said member whereby the pressure exerted by said spring means on said valve head carrying element when said valve head contact with the valve seat in the casing whereby carrying element and said member are in anyw the pressure of said second spring on the spindle given relative position is varied in accordance@ ,swhen thevalve head of said member and the valve with temperature, and a second spring means actseat of the casing are in any given relative posiing between the casing and the spindle urging 5 tion is variedin accordance with the temperature.

the spindle together with the thermal responsive FULLERTON GEORGE element and said member towards a position wherein the valvel head on said member makes GORDON ARMSTRONG. 

